New Owner: Questions

1. Vibration motor: when my phone vibrates there's an odd sound after the vibrate.. it sounds like a metal "ding" or an echo inside the phone due to the aluminum. Is this normal? It sounds off - other aluminum phones don't do this but I'm wondering if it's because of the size..

2. Speakers: this involves the vibration as well (kind of). I noticed when listening to YouTube I can feel the sound bouncing around through the internals of the phone (if that makes sense?). The phone vibrates (different than when receiving a text) when audio is played loudly.. kind of uncomfortable when holding the device. Normal or odd?

Other than those 2 things it's a great device. Awesome display + battery + camera make it an awesome device to own.